LAUSR

Abstract In energy-based fatigue models, in addition to plastic strain energy density calculated from area inside hysteresis loop, positive elastic energy is usually considered. In current elastic energy definitions, mean stress effects in different loading conditions are calculated using different formulations, causing physical inconsistency. In this paper, a new positive elastic energy relationship is suggested. Fatigue data on ZK60, AM50 and Ti-6Al-4V alloys, under constant amplitude at various stress/strain ratios and variable amplitude loads, are employed to evaluate the proposed relationship. It is concluded that this definition yields statistically improved predictions, especially at load cases involving cycles with positive/zero stress ratio.